src/lookups/nisplus.c

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 1995 - 2018 */
   6 /* See the file NOTICE for conditions of use and distribution. */
   7
   8 #include "../exim.h"
   9 #include "lf_functions.h"
  10
  11 #include <rpcsvc/nis.h>
  12
  13
  14 /*************************************************
  15 *              Open entry point                  *
  16 *************************************************/
  17
  18 /* See local README for interface description. */
  19
  20 static void *
  21 nisplus_open(uschar *filename, uschar **errmsg)
  22 {
  23 return (void *)(1);    /* Just return something non-null */
  24 }
  25
  26
  27
  28 /*************************************************
  29 *               Find entry point                 *
  30 *************************************************/
  31
  32 /* See local README for interface description. The format of queries for a
  33 NIS+ search is
  34
  35   [field=value,...],table-name
  36 or
  37   [field=value,...],table-name:result-field-name
  38
  39 in other words, a normal NIS+ "indexed name", with an optional result field
  40 name tagged on the end after a colon. If there is no result-field name, the
  41 yield is the concatenation of all the fields, preceded by their names and an
  42 equals sign. */
  43
  44 static int
  45 nisplus_find(void *handle, uschar *filename, const uschar *query, int length,
  46   uschar **result, uschar **errmsg, uint *do_cache)
  47 {
  48 int i;
  49 int error_error = FAIL;
  50 const uschar * field_name = NULL;
  51 nis_result *nrt = NULL;
  52 nis_result *nre = NULL;
  53 nis_object *tno, *eno;
  54 struct entry_obj *eo;
  55 struct table_obj *ta;
  56 const uschar * p = query + length;
  57 gstring * yield = NULL;
  58
  59 do_cache = do_cache;   /* Placate picky compilers */
  60
  61 /* Search backwards for a colon to see if a result field name
  62 has been given. */
  63
  64 while (p > query && p[-1] != ':') p--;
  65
  66 if (p > query)          /* get the query without the result-field */
  67   {
  68   uint len = p-1 - query;
  69   field_name = p;
  70   query = string_copyn(query, len);
  71   p = query + len;
  72   }
  73 else
  74   p = query + length;
  75
  76 /* Now search backwards to find the comma that starts the
  77 table name. */
  78
  79 while (p > query && p[-1] != ',') p--;
  80 if (p <= query)
  81   {
  82   *errmsg = US"NIS+ query malformed";
  83   error_error = DEFER;
  84   goto NISPLUS_EXIT;
  85   }
  86
  87 /* Look up the data for the table, in order to get the field names,
  88 check that we got back a table, and set up pointers so the field
  89 names can be scanned. */
  90
  91 nrt = nis_lookup(CS p, EXPAND_NAME | NO_CACHE);
  92 if (nrt->status != NIS_SUCCESS)
  93   {
  94   *errmsg = string_sprintf("NIS+ error accessing %s table: %s", p,
  95     nis_sperrno(nrt->status));
  96   if (nrt->status != NIS_NOTFOUND && nrt->status != NIS_NOSUCHTABLE)
  97     error_error = DEFER;
  98   goto NISPLUS_EXIT;
  99   }
 100 tno = nrt->objects.objects_val;
 101 if (tno->zo_data.zo_type != TABLE_OBJ)
 102   {
 103   *errmsg = string_sprintf("NIS+ error: %s is not a table", p);
 104   goto NISPLUS_EXIT;
 105   }
 106 ta = &tno->zo_data.objdata_u.ta_data;
 107
 108 /* Now look up the entry in the table, check that we got precisely one
 109 object and that it is a table entry. */
 110
 111 nre = nis_list(CS query, EXPAND_NAME, NULL, NULL);
 112 if (nre->status != NIS_SUCCESS)
 113   {
 114   *errmsg = string_sprintf("NIS+ error accessing entry %s: %s",
 115     query, nis_sperrno(nre->status));
 116   goto NISPLUS_EXIT;
 117   }
 118 if (nre->objects.objects_len > 1)
 119   {
 120   *errmsg = string_sprintf("NIS+ returned more than one object for %s",
 121     query);
 122   goto NISPLUS_EXIT;
 123   }
 124 else if (nre->objects.objects_len < 1)
 125   {
 126   *errmsg = string_sprintf("NIS+ returned no data for %s", query);
 127   goto NISPLUS_EXIT;
 128   }
 129 eno = nre->objects.objects_val;
 130 if (eno->zo_data.zo_type != ENTRY_OBJ)
 131   {
 132   *errmsg = string_sprintf("NIS+ error: %s is not an entry", query);
 133   goto NISPLUS_EXIT;
 134   }
 135
 136 /* Scan the columns in the entry and in the table. If a result field
 137 was given, look for that field; otherwise concatenate all the fields
 138 with their names. */
 139
 140 eo = &(eno->zo_data.objdata_u.en_data);
 141 for (i = 0; i < eo->en_cols.en_cols_len; i++)
 142   {
 143   table_col *tc = ta->ta_cols.ta_cols_val + i;
 144   entry_col *ec = eo->en_cols.en_cols_val + i;
 145   int len = ec->ec_value.ec_value_len;
 146   uschar *value = US ec->ec_value.ec_value_val;
 147
 148   /* The value may be NULL for a zero-length field. Turn this into an
 149   empty string for consistency. Remove trailing whitespace and zero
 150   bytes. */
 151
 152   if (value == NULL) value = US""; else
 153     while (len > 0 && (value[len-1] == 0 || isspace(value[len-1])))
 154       len--;
 155
 156   /* Concatenate all fields if no specific one selected */
 157
 158   if (!field_name)
 159     {
 160     yield = string_cat (yield, tc->tc_name);
 161     yield = string_catn(yield, US"=", 1);
 162
 163     /* Quote the value if it contains spaces or is empty */
 164
 165     if (value[0] == 0 || Ustrchr(value, ' ') != NULL)
 166       {
 167       int j;
 168       yield = string_catn(yield, US"\"", 1);
 169       for (j = 0; j < len; j++)
 170         {
 171         if (value[j] == '\"' || value[j] == '\\')
 172           yield = string_catn(yield, US"\\", 1);
 173         yield = string_catn(yield, value+j, 1);
 174         }
 175       yield = string_catn(yield, US"\"", 1);
 176       }
 177     else
 178       yield = string_catn(yield, value, len);
 179
 180     yield = string_catn(yield, US" ", 1);
 181     }
 182
 183   /* When the specified field is found, grab its data and finish */
 184
 185   else if (Ustrcmp(field_name, tc->tc_name) == 0)
 186     {
 187     yield = string_catn(yield, value, len);
 188     goto NISPLUS_EXIT;
 189     }
 190   }
 191
 192 /* Error if a field name was specified and we didn't find it; if no
 193 field name, ensure the concatenated data is zero-terminated. */
 194
 195 if (field_name)
 196   *errmsg = string_sprintf("NIS+ field %s not found for %s", field_name,
 197     query);
 198 else
 199   store_reset(yield->s + yield->ptr + 1);
 200
 201 /* Free result store before finishing. */
 202
 203 NISPLUS_EXIT:
 204 if (nrt) nis_freeresult(nrt);
 205 if (nre) nis_freeresult(nre);
 206
 207 if (yield)
 208   {
 209   *result = string_from_gstring(yield);
 210   return OK;
 211   }
 212
 213 return error_error;      /* FAIL or DEFER */
 214 }
 215
 216
 217
 218 /*************************************************
 219 *               Quote entry point                *
 220 *************************************************/
 221
 222 /* The only quoting that is necessary for NIS+ is to double any doublequote
 223 characters. No options are recognized.
 224
 225 Arguments:
 226   s          the string to be quoted
 227   opt        additional option text or NULL if none
 228
 229 Returns:     the processed string or NULL for a bad option
 230 */
 231
 232 static uschar *
 233 nisplus_quote(uschar *s, uschar *opt)
 234 {
 235 int count = 0;
 236 uschar *quoted;
 237 uschar *t = s;
 238
 239 if (opt != NULL) return NULL;    /* No options recognized */
 240
 241 while (*t != 0) if (*t++ == '\"') count++;
 242 if (count == 0) return s;
 243
 244 t = quoted = store_get(Ustrlen(s) + count + 1);
 245
 246 while (*s != 0)
 247   {
 248   *t++ = *s;
 249   if (*s++ == '\"') *t++ = '\"';
 250   }
 251
 252 *t = 0;
 253 return quoted;
 254 }
 255
 256
 257 /*************************************************
 258 *         Version reporting entry point          *
 259 *************************************************/
 260
 261 /* See local README for interface description. */
 262
 263 #include "../version.h"
 264
 265 void
 266 nisplus_version_report(FILE *f)
 267 {
 268 #ifdef DYNLOOKUP
 269 fprintf(f, "Library version: NIS+: Exim version %s\n", EXIM_VERSION_STR);
 270 #endif
 271 }
 272
 273
 274 static lookup_info _lookup_info = {
 275   US"nisplus",                   /* lookup name */
 276   lookup_querystyle,             /* query-style lookup */
 277   nisplus_open,                  /* open function */
 278   NULL,                          /* check function */
 279   nisplus_find,                  /* find function */
 280   NULL,                          /* no close function */
 281   NULL,                          /* no tidy function */
 282   nisplus_quote,                 /* quoting function */
 283   nisplus_version_report         /* version reporting */
 284 };
 285
 286 #ifdef DYNLOOKUP
 287 #define nisplus_lookup_module_info _lookup_module_info
 288 #endif
 289
 290 static lookup_info *_lookup_list[] = { &_lookup_info };
 291 lookup_module_info nisplus_lookup_module_info = { LOOKUP_MODULE_INFO_MAGIC, _lookup_list, 1 };
 292
 293 /* End of lookups/nisplus.c */